Molar solubility is defined as the maximum number of moles of solute that can dissolve in 1 liter of solvent. As an illustration, a certain amount of Sodium Chloride salt is added to 1 liter of water.
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00:00Molar solubility is defined as the maximum number of moles of solute that can dissolve in 1 liter of solvent.
00:15As an illustration, a certain amount of sodium chloride salt is added to 1 liter of water.
00:22Some of the salt molecules are ionized into Na plus ions and Cl minus ions.
00:28While the others are still in the form of NaCl molecules.
00:34When the amount of salt is increased, it turns out that the number of ionized molecules is still the same.
00:42The remaining salt molecules are still in the form of NaCl molecules.
00:49Well, the number of ionized salt molecules is the maximum mole value of solute.
00:56The molar solubility value of NaCl is 6.41 moles per liter.
01:03This means that in 1 liter of water there are 6.41 moles of NaCl molecules that can be ionized in the water.
01:12Based on the NaCl ionization equation, in the solution there will be 6.41 moles of Na plus ions
01:21and 6.41 moles of Cl minus ions.
01:28If these ionized NaCl molecules are weighed, their mass is 375 grams.
01:36From here we get the solubility of sodium chloride salt is 375 grams per liter.
01:44In other words, the solubility of NaCl 375 grams per liter corresponds to the molar solubility of NaCl 6.41 moles per liter.
01:58These two quantities are connected by the equation, the solubility of a substance is equal to the relative molecular mass of the substance multiplied by the molar solubility of the substance.
02:11To understand this concept, calculate the molar solubility of the following substances.
02:19OK, in case A, the solubility of manganese chloride is 739 grams per liter.
02:27The relative molecular mass of MnCl2 is 55 plus 35.5.
02:35This calculation is 126 grams per mole.
02:41The molar solubility of MnCl2 is the solubility divided by the relative molecular mass.
02:48Plugging in all the values, the result is 5.865 moles per liter.
02:57In case B, the solubility of barium manganate is 0.036 grams per liter.
03:05The relative molecular mass of BaMnO4 is 137.3 plus 55 plus 4 times 16.
03:14This calculation is 256.3 grams per mole.
03:20The molar solubility of barium manganate is the solubility divided by the relative molecular mass.
03:27Plugging in all the values, the result is equal to 1.4 times 10 to the power of negative 4 moles per liter.
03:38In case C, the solubility of magnesium sulfate is 180 grams per liter.
03:47The relative molecular mass of MgSO4 is 24.3 plus 32 plus 4 times 16.
03:56This calculation is 120.3 grams per mole.
04:02The molar solubility of magnesium sulfate is the solubility divided by the relative molecular mass.
04:09Plugging in all the values, the result is equal to 1.5 moles per liter.
04:17Yup, hopefully this tutorial can give you an idea of what molar solubility is.
04:23And, don't forget to follow this channel.